a) Field of the Invention
The present invention relates to control apparatus and method for an automotive vehicle and, more particularly, relates to inter-vehicle distance control apparatus and method for controlling an inter-vehicle distance from the vehicle to another preceding vehicle traveling ahead of the vehicle, maintaining the inter-vehicle distance between the vehicle and the preceding vehicle at a determined distance value to follow up the preceding vehicle.
b) Description of the Related Art
A Japanese Patent Application First Publication No. Heisei 6-8747 published on Jan. 14, 1994 exemplifies a previously proposed vehicular inter-vehicle distance controlling apparatus.
In the previously proposed inter-vehicle distance controlling apparatus disclosed in the above-identified Japanese Patent Application Publication, a target vehicle speed is set, an actual inter-vehicle distance between the vehicle and another preceding vehicle traveling ahead of the vehicle is measured, and a target inter-vehicle distance to the other preceding vehicle is calculated according to the instantaneous vehicle speed.
When the calculated target inter-vehicle distance is larger (longer) than the actual inter-vehicle distance, a vehicular speed controller determines that the vehicle is too be approached to the other preceding vehicle and performs a deceleration control to decelerate the vehicle.
On the contrary, when the calculated target inter-vehicle distance is smaller (shorter) than the actual inter-vehicle distance, the vehicular speed controller determines that the vehicle is running at a safe position with respect to the other preceding vehicle and performs an acceleration control with an acceleration which is in accordance with a difference between the target vehicle speed and the actual vehicle speed.
Furthermore, when a right winker of the vehicle indicates that the vehicle is running at a right direction with respect to the width of the vehicle from an output signal of a winker switch and a steering angular displacement is equal to or in excess of a predetermined value, the vehicular speed controller recognizes that the vehicle is changing a traffic lane to another traffic lane in order to turn over the preceding vehicle and calculates the target inter-vehicle distance on the basis of the instantaneous vehicle speed. When the calculated target inter-vehicle distance is larger than the actual inter-vehicle distance detected by a radar unit which constitutes the inter-vehicle distance detector, the vehicular speed controller determines that the vehicle is too be approached to the other preceding vehicle and performs the deceleration control. When the target inter-vehicle distance is smaller (shorter) than the actual inter-vehicle distance, the controller determines that the vehicle is running at a safe distance with respect to the preceding vehicle so that the target vehicle velocity is incrementally corrected to perform the acceleration control.